Queue simulation of cyclic construction operations

Abstract

Cyclic construction operations may be modelled in terms of the waiting times of the entities (typically equipment, plant, materials or manpower) that repeatedly pass through the various phases of the cycle. The relevant model involves recursive expressions linking the waiting times of successive cycles. This permits a Monte Carlo type simulation to be carried out and represents an alternative method to conventional event or time-oriented simulation and queueing theory. The elementary form of the recursive expressions for the waiting times results in a short computer program and minimal computer demands, enabling the simulation to be carried out on the smallest of microcomputers. The paper develops the simulation approach and makes a comparison with queueing theory. Both random sampling and a variance reduction technique are used. Models are developed for earthmovmg, quarrying and open-cut mining applications in elementary cycle form and multiple phase form.

Keywords:

• simulation
• queues
• cyclic operations
• earthmoving
• mining

Additional information

Notes on contributors

D. G. Carmichael

(Formerly of Department of Civil Engineering, The University of Western Australia)